Objective: To characterize the interrelationships between the structure, the function and the cellular environment of two molecules involved in biological transport processes - cytochrome c (electron transferring properties) and valinomycin (ion transporting abilities). Approach: The interactions of ferricytochrome c with chromous ion, (what is the nature of the site of electron introduction?) are being studied. In other experiments, the structure of cytochrome c complexes with phospholipids in aqueous and organic media are being examined. Attempts will be made to correlate the results of these experiments and to establish the environmental impositions on, and other conditions, controlling the structure and reactivity of this protein. The complexing of valinomycin with cations is being studied with respect to ion pairing of complexes (do these antibiotics act as metabolic anion transporters also?), structure of complexes and relationship of environment to structure and reactivity.